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Self-unloaders cargo loading guideline- various restrictions & related considerations Voyage orders, draft restrictions, various grades of cargo and rates:
A copy of the Charter Party applicable to your vessel is to be handed to the Master as soon as possible,
where the vessel is engaged/fixed recently. Where long term contracts of affreightment exists, you
may already have a copy of such onboard. If these are not available, all the necessary information will
be forwarded in the form of Voyage Instructions or Orders.

These orders will describe the berths,
guaranteed depth, arrival draft, shore loading facility and rates, shore take-away facility and rate,
quantity of uplift of cargo, charterers, shippers, consignees and agents etc. If you require clarification
or advice on any aspect of the concise voyage instructions or the Charter Party you are to contact the
relevant Management Office.

The Master is responsible for ensuring that the vessel performs as described in the Charter Party at all
times. The Company will advise the Owners of any inability to comply with the requirements of the
Charter Party, and enter into discussions with the Charterers. Similarly, the Master is to ensure that
any instruction or requests from the charterers complies with the requirements of the vessel, Master
and crew as defined in the Charter Party, otherwise advice is to be obtained from the relevant
Management Office.

The vessels draft with the density, and restriction of depth is also to be declared on arrival at the
discharge port.

The rate of loading or discharging will be stated as a figure per working day, or the actual minimum
rate, or to the ground in the case of the vessels rated capacity to discharge. If the Master determines
that the vessel is in any way unable to achieve this rate, he must notify the relevant Management office
immediately with the reasons.

The concise voyage instructions will also contain information of the cargo itself, the type, their grades
and quantities. Loading the various grades in the proper sequential order to avoid contamination or
mixing, their segregation, etc. should be clarified in the instructions. The sensitive grade/s should also
be specially identified.

Fig:self unloader components ready for operation

The grade of the optional quantity is to be stated/identified and ideally used for
trimming the vessel. The sequence of discharging of the various grades must be established and
followed. The procedure at a change of grade is to be strictly adhered to. When submitting the
loading plan to the shore terminal, agreement to the figures planned by the terminal must be ensured,
and also that they have not changed any figures or grades which will require revision of the loading
plan. The relevant Management Office must also be notified, and the loading plan prepared again to
the satisfaction of the Master.

THE BILL OF LADING

The Bill of Lading sometimes used in the self unloading vessel trade may be of format agreed upon by
the Owners, Shippers and the Charterers. If the Master is in any doubt regarding any aspect of the Bill
of Lading, he must contact the Company before signing the same. Letters of Indemnity are not used in
this trade, and the Master must contact the relevant Management Office if he is issued one.

The Owners have expressed that their customers on the USA coastal trade are known, and the Master
must not await the signed B/L and other instructions before releasing the cargo. This is a non-standard
procedure, and if in doubt the Master is to contact the Company or Owners for clarification.

WATER-LINE TO TOP OF HATCH COAMING HEIGHT RESTRICTIONS

The height from the water-line to the top of the hatch coaming, is of importance at the load port to
determine if the height of the shore loader in a given tidal level is sufficient to commence loading, or if
the vessel will have sufficient clearance underneath the loader.

Due to the trim of the vessel, this height varies hold to hold and loading may be planned to commence
accordingly at an after hold, and transferred simultaneously to a centre hold using the SUL system. It
is important to find out from the local agents or shippers the details of the loading arm before engaging
a cargo from any port.

The term ‘air draft’ applies to the height of the highest point on the vessel from the water-line e.g. the
top of the radar mast and is required when determining if the vessel can pass under bridges in rivers
and waterways.

Air-drafts must be calculated in full ballast and unballasted condition, and/or other possible present
conditions of arrival or departure to determine a safe passage.

THE STAGES OF SUL LOADING

Understanding the voyage instructions and preparing the load plan.

Preparation of holds.

Inspection of holds to ensure that all residue of the previous cargo is removed.

Testing all communications.

Establishing communications with the shore terminal and completing the ship-shore checklist.

Hand over and explanation of the load plan to the shore personnel in charge of loading.

Completing the Ship to Shore

Completing the Cargo loading/preparation

Commencement of loading.

Carrying out the boom banking procedure.

Loading and de-ballasting/stripping as per sequences planned.

Completing the watch handover checklist

Draft Checks, Trimming sequences.

Completion of trimming.

Draft checks and calculations are to be carried out and the drafts closely monitored visually, prior to the
starting of the trimming sequence, with about say 5000 m/tons remaining. This allows corrections to
achieve the final planned draft. Corrections may have to be made where the shore loader weight
counter has an error, or where the cargo contains an unexpected amount of water or has been
washed.

The tonnage of material on the shore belt when trimming must be taken into account as the shore
loader will be carrying a large amount of cargo, which has to be run out into the ships hold. The
quantity has to be ascertained before trimming, and allowed for when providing the completing
tonnage requirement to the shore loader. If this is not carried out the vessel may be in an overloaded
condition.

Bulldozers or similar machines are not to be allowed into the holds at any stage of loading in efforts to
compact the cargo, as this will affect the free flow ability of the cargo. It is however permissible in the
case of coal cargoes where compacting will reduce the trapped air, and lower the fire risk. Before this
procedure is carried out the Master must contact the relevant Management Office for their consent.
If in the event of grain carriage, and fumigation is required, safety measures will have to be considered
as the entire tunnel will be affected with poisonous gas.

SEGREGATION OF VARIOUS GRADES (LOADING)

The planning and segregation of grades is very important for the avoidance of cargo
claims.
The sequence of loading of the various grades must be agreed with shippers and shore personnel. The
planned sequence of the ‘Loading Plan’ must be accepted and approved by the Shore Terminal. All
means of communications between ship and shore are to be tested. Clear information and instructions
must be provided by the shore personnel at completion and change of grade.

The Duty Officer is
required to visibly ensure that the shore loading/conveyor system is absolutely clear of the previous
grade and to request the shore to verbally confirm the same. If, when inspecting the cargo loaded in
the holds, any contamination or non uniformity in the cargo is observed, this must be immediately
brought to the notice of the Shore Foreman or authorised person. If the doubt persists the Company
must be informed.

LOADING/STABILITY MANUALS

The Master is to read, understand, and comply with, the limitations stated in the vessels Loading and
Stability manual, which is certified by Classification.

The following limitations and/or restrictions are to be complied with:

1. Load density of each hold, or the maximum allowable homogenous tonnage in each hold.

2. The alternate holds which may be kept empty, and the maximum allowable draft in this
condition.

3. If any single hold can be left empty.

4. Maximum permissible load on an unsupported transverse bulkhead.

5. Limits of bending moments and shearing forces.

The mandatory conditions must be referred to. The minimum fluid GM attained in these conditions is
to be considered as the lowest that is permissible, even though the vessel may be well within the limits
set for bulk carriers in general.

BOOM BANKING PROCEDURE

The boom banking procedure is a method for creating a counterweight for the out swung boom at the
start of loading. In effect this is to counter or compensate for the list which occurs due to the offshore
slewing of the boom. This is mainly the case for straight and articulated booms, as these are in the
way of the shore loader, and obstruct the loading of after holds.

The average weight of the boom can amount to 250 metric tons. Swinging the boom outboard will
cause a list, which is detrimental to the operation and the boom itself. A ‘bank’ or counterweight
therefore has to be made by using the cargo being loaded in a designated hold forward of the boom head, preferably at the start of loading.

Ballast must not be used to compensate and is to be evenly
pumped out. To form this bank, the boom is to be swung slowly outboard, whilst the shore loader is
loading on the extreme inboard inshore side of the designated hold. Ideally, the ballast on both sides
should be almost even in all tanks, so that when the boom is being swung back prior to trimming or
other planned sequence, the list can be compensated by cargo itself. At this stage the ballast is to be
pumped out and stripping completed. Sometimes, when the boom is brought back to centre it may
obstruct the shore loader for the holds in the trimming sequence.

In such a case the boom is to be
moved as near as possible to the hatch coaming. A small balance of cargo must then be retained to
correct the list after bringing the boom to the centre, by loading this small balance, say 50 tons into a
forward hold.

When planning an intermediate run (sequence) in the hold with the ‘bank’ care must be taken not to
overwhelm the banked amount, especially when loading lighter cargoes like coal at a good rate. This
may cause the vessel to list at end of that run.

LISTING

The reasons for the vessel listing during cargo operations may be as the result of:

Uneven de-ballasting.

Water re-entering a stripped tank, owing to a faulty valve.

The loss of a boom bank.

Uneven loading, due to faulty listometer lights.

Transfer of bunkers.

The cause for the vessels list must be ascertained and corrected immediately

SUDDEN LISTING

The vessel may suddenly list while loading lighter cargoes due to:

The reduction of the GM caused by the high piles of voluminous cargo.

Loss of the boom counterweight.

Free Surface Effect, or the slack water in ballast tanks that forms a wedge to the listed side.

Outstretched boom.

Sudden lists can become more progressive if not checked immediately. The boom must not be moved
in this listed condition as overloading and resultant hydraulic pipe failure may occur, complicating the
situation.

The cargo loading must be stopped and measures taken to increase the GM by refilling a DB tank on
the lower side, and then loading some cargo in the empty hold. When the list is less than 2 degrees,
the Boom can be brought slowly inboard as much as possible to further reduce the list. The vessel is
however still in a sensitive condition, and efforts must be made to strip out all the slack tanks.